Piston ring



H. STOFFERS.

PISTGN RING.

APPLlcATloN- FILED MAY 12. 1.921.

1,41 8,21 1 Patented May '30, 1922.

INVENTOR ATTORNEYS TES ' ristron RING.

naiaeii.

Application filed May 12, 1921.

To all fw tom t may concern:

Be it known that l, HENRY S'rorrnns, a citizenV of the United States, and a resident of Newark, in the county of Essex and State of N ew Jersey, have invented a new and 1mproved Piston Ring, of which the following is a full, clear, and exact description.

This invention relates to piston rings for internal combustion engines and refers more particularly to hammered piston rings, the same being constructed in accordance with the method set forth in my application Se rial No. 386,738, allowed December 30, 1921,).

1n constructing hammered piston rings for increasing` the resiliency of the same, the density or grain of the metal is compressed by the impact of the blows, and it has been found by experiment that slightly raised and hardened spots are formed on the outer peripheral bearing face of the ring. These hardened spots tend to injure vthe walls of the cylinder by forming grooves or otherwise mutilating the same, resulting in the destruction and impairment of the compression of the engine.

It is therefore an object of the present invention to provide a ring which is so constructed as to prevent the forniation of hardened spots on the bearing face of the ring which coacts with the'cylinder walls.

Another object in view resides in the provision of an improved form of hammered 'ring which does not materially add to the expense of its production nor increase the labor incident thereto.

lVith the above recited and other objects in view, the invention resides in the novel construction set forth in the following specitication, pointed out in the appended claims and illustrated in the accompanying drawings, it being understood that the right is reserved to embodiments other than those actually illustrated herein to the full eXtent indicated by the general meaning in which the terms are expressed and by variations in the phraseology of the saine.

1n the drawings- Figure 1 is a sectional View through a piston ring constructed in accordance with the invention.

Figs. 2, 3 and 4 are diagrammatic illustrations of several forms in which the ring may be constructed.

Fig. 5 is a diagrammatic view of the old and known construction of a hammered piston ring.

Specification of 'Letters Patent.

Patented May 30, 1922.

serial ne. 468,888.

Referring' to Fig. 5 of the drawings, it will be seen that the ring 10 of common construction is of rectangular formation in cross section. lin hammering a ring ,of 'this type for the purpose of increasing its resiliency, the blows during the hammering operation are recorded at the points 11 resulting in the compression of the grain of the metal to a greater density than the remainder, as illustrated by the shaded portion 12. As these rings are necessarily of thin material, the increase in density caused by the impact of the blows extends through the ring to its outer peripheral bearing surface13, resulting in hardened and slightly raised spots or portions 141-. When the ring is applied to a piston and arranged in a cylinder it is obvious that the spots or portion 14 will tend to scratch or groove the inner walls of the cylinder resulting in loss of conipression and other objectionable features.

Referring' to the improved form of ring illustrated in Figs. 1 and 2, the inner pee riphery of the ring is provided with a substantially V-shaped annular groove v15, the

angular walls 16 of which are disposed at such an angle with respect to the bearing surface as to cause the compression and increase in the density of tl'iegrain of the metal to either become lost prior to reaching the outer surfaces or to form the hardened and raised spots or portion at the terminal of said compressed grain to appear on the upper and lower edges 17 of the ring. The compressed portions illustrating the increase in the density of the metal is illustrated at 18 and it will be noted that where the blow is recorded on the angular faces or walls 16 the increase in density is of a greater Width and is of gradually decreasing width therefrom to the terminal of said compressed grain.

In F ig. 3 a slightly modilied form of groove is illustrated, and in this instance the groove 15 is provided with a central dis posed face 162L substantially parallel to thebearing face of the ring and angularly disposed faces 172L arranged at an opposite inclination with respect to each other.

1n Fig. a a still further modification of which the ring is capable is illustrated, and in this instance the groove 15b is provided with oppositely inclined angular-ly disposed faces 161 which extend from'their juncture entirely to the upper and lower edges of the ring.

Having thus described my invention, what I claim is:

1. As an article of manufacture, a piston ring provided with an inner annular groove having angular-ly disposed faces and increased grain density extending at a right angle to the angular faces of the groove.

2. As an article of manufacture, a piston ring provided with an inner annular groove having angularly disposed faces and increased grain density compressed at an angle toward its outer edges, the Width of said compressed grain density gradually decreasing toward said outer edges.

3. As an article of manufacture, a piston 15 ring provided With an inner peripheral groove having oppositely inclined angularly disposed faces, the angularity of said faces serving to transmit increased grain density caused by the impact of hammer blows on 20 said faces to extend toward the upper and lower edges of the ring.

HENRY sfrorrnns. 

